DE102010006384A1 - Repair method for a composite component for an aircraft, composite component for an aircraft and apparatus for repairing a composite component for an aircraft - Google Patents

Abstract

The invention relates to a repair method for a composite component (1) for an aircraft with a base body (2) made of a fiber composite material and a metal part (3) connected to the base body (2), measures being provided so that the temperature in the area of the connection of the Metal part (3) with the base body (2) does not exceed a predetermined value, and additional material (5) is applied to the metal part (3) with thermal energy supply.

Description

The invention relates to a repair method for a composite component for an aircraft, a composite component for an aircraft and a device for repairing a composite component for an aircraft with the features of one of the preambles of claims 1, 13 or 15.

Composite components are preferably used in aircraft if the parts are to have a high strength with a low dead weight. These are z. As parts of the wings, parts of the fuselage and in particular the blades in the aircraft drives.

Shovels for aircraft drives have z. B. a light but high strength body made of a fiber composite material such. As a carbon fiber reinforced plastic (CFRP) or a fiber reinforced metal (CMC), and a base body of the blade at least on the flow inlet side covering metal fitting of a high strength metal such. As a titanium alloy, on. The base body of the fiber composite material has the advantage that it has a very high strength at a very low weight, while the metal fitting has a very hard surface and has the task of erosion resistance and impact resistance of the blade against impinging foreign bodies, such as. B. birds, increase.

Such a blade is z. B. from the DE 10 2006 061 915 A1 known.

The metal fittings on the blades are subject to unavoidable wear during operation of the aircraft engine and must therefore be replaced during maintenance of the aircraft engine at regular intervals. For this purpose, the metal fittings must be detached from the body and replaced with new or repaired metal fittings. Both the detachment of the metal fitting to be replaced as well as the connection of the new metal fitting with the body are connected due to the high demands on the connection with a high cost and cost. Furthermore, this repair method requires that identical replacement metal fittings are available, so that such maintenance can only be performed in specific locations or requires a corresponding logistical effort.

The same applies to composite components in use as parts of the wings or the fuselage, in which case metal parts for connecting the composite component to adjacent parts or for increasing the inherent rigidity are provided on the main body of the fiber composite material.

The object of the invention is to provide a cost-effective with little effort associated repair method for a composite component for an aircraft, a cost repaired composite component for an aircraft and a device by means of which a composite component for an aircraft can be repaired inexpensively.

To achieve the object, a repair method according to claim 1, a composite component according to claim 13 and a device according to claim 15 is proposed. Further preferred embodiments of the invention can be found in the subclaims, the figures and the associated description.

According to claim 1, a repair method for a composite component for an aircraft is proposed with a base body made of a fiber composite material and connected to the main body metal part, are provided in the measures, so that the temperature in the region of the connection of the metal part with the main body a does not exceed the predetermined value, and additional material is applied to the metal part under thermal energy supply. The particular advantage of the invention is the fact that the metal part for the repair does not have to be separated from the body. The repair of the composite component takes place thereby, by additional material is applied to the metal part with the supply of thermal energy. The thermal energy allows a fusion of the applied material with the metal part to an enlarged metal part, wherein by the applied material z. B. erosion points can be replenished. The thermal energy is introduced at a process temperature of about 2000 degrees Celsius in the composite component. Since the build-up welding takes place over a longer period of time, a very high thermal energy is introduced into the composite component. So that the connection between the base body and the metal part is not canceled or damaged by the thermal energy introduced into the composite component, measures are taken at the same time to prevent a predetermined temperature in the region of the connection between the base body and the metal part being exceeded ,

The composite component does not have to be disassembled consuming for the proposed repair process and then reassembled, so that the repair process is very inexpensive. In addition, no identical replacement metal part is required for the repair process, so that the Repair can be performed virtually at any maintenance location, provided there is a means for applying the material, and it can be ensured that the temperature does not exceed the predetermined temperature. Preferred methods for applying the material are, for. As electron beam surfacing, laser cladding, cold gas spraying or friction welding. Furthermore, it is possible to repair composite components by the repair process, in which the metal part can not be separated or only by a partial damage of the body of this.

The value of the predetermined temperature should be 70 to 200 degrees Celsius, preferably 80 degrees Celsius, so that no heat-related damage occurs at the base body or at the interface between the base body and the metal part.

It is further proposed that at least one temperature sensor be provided in the base body and / or the metal part, with which the temperature in the region of the connection of the metal part to the base body during the application of the material is measured. By using a temperature sensor for measuring the temperature in the region of the connection of the metal part and the main body can be ensured by online monitoring that the temperature does not exceed the predetermined temperature in any case, even during the application of the material.

Alternatively or additionally, the temperature of the composite component can also be measured without contact with an external device. Such non-contact devices would z. As thermal imaging cameras, pyrometers or quotient pyrometer. The advantage of such non-contact devices is that the composite component itself does not have to be changed or the repair process can thereby be applied to any not specially prepared for the repair process composite components. Furthermore, the temperature measuring location can thereby also be changed during the repair of the composite component.

In particular, it makes sense if the application of the material is also controlled as a function of the temperature of the composite component. The thermal energy introduced by the application of the material is the cause of the temperature increase at the bonding surface between the metal part and the main body, so that the exceeding of the predetermined temperature can also be prevented by reducing the application rate of the material. In extreme cases, the application of the material can also be interrupted for a short time.

Furthermore, the composite component can be cooled during the application of the material by means of a cooling device, so that the temperature in the composite component can also be actively reduced by targeted heat removal.

Such a cooling device may, for. B. be formed by one or more of a cooling medium flowed through cooling channels in the base body and / or the metal part or by at least one external directed to the composite component cooling surface. A cooling device with cooling channels allows a very high and targeted internal heat dissipation, while no structural changes to the composite components must be made by the use of external cooling surfaces.

In this case, the cooling device can be controlled in dependence on the temperature of the composite component by z. B. is activated only when exceeding a predefined below the predetermined temperature limit temperature. In the event that the predefined temperature is not exceeded, heat removal via the cooling device is not required and the energy required to operate the cooling device can be saved.

In particular, the cooling device can be arranged such that the generated heat flow in the composite component is directed away from the main body of the composite component. The proposed arrangement of the cooling device and the associated management of the heat flow, the temperature load of the body is further reduced.

A further preferred embodiment of the invention can be seen in the fact that the temperature in the composite component is calculated computer-assisted before the application of the material, and the application of the material and / or the cooling device is controlled as a function of the calculated temperature. In knowledge of the temperature distribution, it is z. B. possible to close by measuring at another location of the body or the metal part to the temperature at the interface between the body and the metal part. In addition, it can be determined beforehand by means of such a calculation under which circumstances the predetermined temperature is exceeded at all. In the event that such a calculation indicates that the predetermined temperature at the interface is not exceeded at any time of material application, e.g. B. due to a large wall thickness of the metal part, can be completely dispensed with a cooling of the composite component during the repair process.

It is further proposed that the applied material be partially removed from the surface of the metal part in a subsequent operation to create a predetermined surface contour of the composite component. The material is deliberately applied thicker, the surface contour and the other surface properties are just realized by a post-processing.

Further, a composite component for an aircraft with a base made of a fiber composite material and a metal part connected to the base body is proposed to solve the problem, wherein the metal part was repaired according to one of the repair method of claims 1 to 12. Such a composite component may be a spare part processed independently of a particular aircraft, which may be reused in any particular type of aircraft. As a result, the composite components can be refurbished at low cost in advance in a larger quantity and then used further as functional replacement parts.

In particular, the composite component may be a blade for an aircraft propulsion, wherein the metal part is formed in this case by a metal fitting covering the blade at least on the flow inlet side. The blades and in particular the metal fittings arranged on the blades are subject to increased erosion of the surface due to their load and flow, so that the repair method used according to the invention by the application of additional material to the surface of the metal fitting is particularly suitable for repairing erosion damage to the metal fittings ,

Further, a device for repairing a composite component for an aircraft with a base body made of a fiber composite material and a metal body connected to the main body is proposed to solve the problem, wherein the device comprises a cooling device for heat dissipation from the composite component and a device for applying material to the metal part having a supply of thermal energy. By means of such a device composite components can be set particularly inexpensive repair without a spare part is required to repair the composite component. The logistical effort for the maintenance of aircraft can be significantly reduced.

The cooling device can be formed by external cooling surfaces, which are in a fixed spatial assignment to the composite component. By standing in a fixed spatial allocation external cooling surfaces, it is possible to control the composite component controlled at a defined point while dissipating a defined amount of heat. The composite component itself need not be structurally altered by the use of external cooling surfaces in the device.

Alternatively, the cooling device may also be formed by at least one cooling channel through which a cooling medium flows in the base body and / or the metal fitting, in which case connections for connecting the cooling channel to a coolant supply and a coolant discharge are provided in the device.

The invention will be explained in more detail with reference to a preferred embodiment. The figures show in detail:

1 : A trained as a composite component blade of an aircraft engine;

2 : Shovel out 1 in the view in the cutting direction BB with a metal fitting with material applied thereto by build-up welding;

3 : Shovel out 1 in the view in the cutting direction BB with a metal fitting with a welded-on repair piece;

4 : Device for repairing a blade;

5 : Fuselage section of an aircraft designed as a composite component with an applied on the metal part additional material.

In the 1 is a composite component 1 to recognize in the form of a blade for an aircraft propulsion. The blade has a base body 2 from a fiber composite material, such as. As a carbon fiber reinforced plastic (CFRP) or a fiber reinforced metal (CMC), and is on the flow inlet side with a metal part 3 provided by which prevents the body 2 damaged by erosion or sudden blows. The metal part 3 is designed as a metal fitting and has a very high erosion resistance, a possible material for the metal part 3 in this case is a titanium alloy.

Furthermore, as well as in the sectional views in the 2 and 3 It can be seen on the surface of the metal part 3 an extra amount of material 5 applied. By the applied material 5 became the surface of the metal fitting damaged by erosion 3 repaired. In the 2 is the additionally applied material 5 by a material application method, such. B. Laser deposition welding, electron beam deposition welding, cold gas spraying or friction welding, applied. The material 5 It is applied under supply of a very high energy, so that the material 5 with the material of the surface of the metal part 3 merges and thus a homogeneous around the material 5 supplemented metal part 3 is formed. The material of the applied material 5 can be identical to the material of the metal part 3 be.

In the 3 is the applied material 5 through a separate with the metal part 3 connected exchange part formed in the form of a preformed blank. The material 5 was also by adding thermal energy to the metal part 3 connected by the replacement part was welded, wherein the material 5 with the metal part 3 merges into a homogeneous part at least at the interface.

Both the applied material 5 in the 2 as well as the material 5 in the 3 may be subjected to post-processing to create the final surface. Furthermore, it may be useful to subject the composite component after processing a heat treatment to compensate for internal material stresses.

Furthermore, both in the 2 as well as in the 3 a cooling device 6 to recognize, by means of which by the application of the material 5 in the composite component 1 , in particular in the metal part 3 , introduced heat is dissipated again, so that the temperature of the composite component 1 in the area of the interface between the main body 2 and the metal part 3 a predetermined value of 70 to 200 degrees Celsius, preferably of 80 degrees Celsius, does not exceed and the connection between the main body 2 and the metal part 3 is not damaged by the heat.

In the 4 is to recognize a device by means of which the proposed repair method is feasible. The blade is fixed in place in the device, and it would also be conceivable to carry out the repair on a blade mounted on the aircraft drive "on-wing". Side of the blade, the transition area between the body 2 and the metal part 3 opposite is a cooling device 6 provided in the form of directed to the blade cooling surfaces. The cooling surfaces are in a fixed spatial relationship to the blade, so that the heat is selectively removed from a portion of the surface of the blade, which is as close as possible to the interface between the base body 2 and the metal part 3 and / or between the metal part 3 and the additional applied material 5 is arranged. There is also a device 9 for applying the additional material 5 by means of a welding electrode 10 intended. The while applying the material 5 in the composite component 1 introduced thermal energy is passed through the cooling device 6 deliberately discharged again, so that a release or delamination of the connection between the metal part 3 and the body 2 by melting the metal part 3 or of the basic body 2 is prevented in the area of the connection. In the blade are in the area of the interface between the main body 2 and the metal part 3 one or more temperature sensors 4 provided with which the temperature of the composite component 1 as close as possible to the connection between the metal part 3 and the base body is measured. The signal of the temperature sensors 4 becomes a control device 8th supplied, which also signal technology with the cooling device 6 and the facility 9 for applying the material 5 connected is. By the control device 8th can both the cooling device 6 as well as the decor 9 depending on the temperature sensors 4 sensed temperature are controlled.

Alternatively, the temperature in the composite component 1 also be simulated computer-assisted before repair, so that the temperatures or the temperature distribution during application of the material 5 are known. In the event that the calculation of the temperature shows that a predetermined temperature, which could lead to a release of the connection, is not exceeded, a heat dissipation via the cooling device 6 also completely eliminated. This can be z. B. be justified by the fact that the wall thickness of the metal part 3 is sufficiently large, or the amount of material to be applied 5 so low is that the associated entry of thermal energy in the composite component 1 does not result in exceeding the predetermined temperature at the interface. Furthermore, it is possible by the known temperature distribution even with an arrangement of the temperature sensors 4 At a location farther from the interface, at least theoretically determine the temperature at the interface by a conversion.

In the 5 an alternative embodiment is shown in which the composite component 1 is formed by a fuselage section of an aircraft. The fuselage section is made of one main body 2 from a fiber composite material of the type already described above and a metal part 3 in the form of an end face to the base body 2 formed metal flange formed. The metal flange is, as can be seen in the sectional view AA, with a mounting opening 11 provided by means of which the fuselage section can be connected to an adjacent component. At the metal part 3 Depending on the type of damage, different surfaces are provided, on each of which material 5 upset has been. So z. B. a section 5.2 on the front side of the metal part 3 or even a section 5.1 in the hole 11 to recognize, on the material 5 was applied to repair wear points. Furthermore, there are different cooling surfaces 6.1 . 6.2 . 6.3 or 6.4 to recognize which of a cooling device, not shown 6 assigned. The effect of the cooling surfaces 6.1 . 6.2 . 6.3 and 6.4 corresponds to the effect of the cooling device 6 from the 4 , The cooling surfaces 6.1 . 6.2 . 6.3 and 6.4 are deliberately arranged so that the through the cooling surfaces 6.1 . 6.2 . 6.3 and 6.4 generated heat flow in the composite component 1 not by the main body 2 runs, and the main body 2 is heated as little as possible.

Alternatively, the cooling device 6 in the in the 4 and 5 illustrated embodiments also by in the metal part 3 and / or in the body 2 provided cooling channels may be formed, which are flowed through by a cooling medium, so that the composite component 1 is cooled from the inside.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102006061915 A1 [0004]

Claims (17)

Repair method for a composite component ( 1 ) for an aircraft with a basic body ( 2 ) of a fiber composite material and one with the main body ( 2 ) connected metal part ( 3 ), characterized in that measures are provided so that the temperature in the region of the connection of the metal part ( 3 ) with the basic body ( 2 ) does not exceed a predetermined value, and on the metal part ( 3 ) additional material ( 5 ) is applied under thermal energy supply. Repair method according to claim 1, characterized in that the value of the predetermined temperature is 70 to 200 degrees Celsius, preferably 80 degrees Celsius. Repair method according to one of the preceding claims, characterized in that in the basic body ( 2 ) and / or the metal part ( 3 ) at least one temperature sensor ( 4 ) is provided, with which the temperature in the region of the connection of the metal part ( 3 ) with the basic body ( 2 ) during the application of the material ( 5 ) is measured. Repair method according to one of the preceding claims, characterized in that the temperature of the composite component ( 1 ) is measured without contact with an external device. Repair method according to one of the preceding claims, characterized in that the application of the material ( 5 ) as a function of the temperature of the composite component ( 1 ) is controlled. Repair method according to one of the preceding claims, characterized in that the composite component ( 1 ) during the application of the material ( 5 ) by means of a cooling device ( 6 ) is cooled. Repair method according to claim 6, characterized in that the cooling device ( 6 ) by one or more cooling channels through which a cooling medium flows in the base body ( 2 ) and / or the metal part ( 3 ) or by at least one external to the composite component ( 1 ) directed cooling surface is formed. Repair method according to one of claims 6 or 7, characterized in that the cooling device ( 6 ) as a function of the temperature of the composite component ( 1 ) is controlled. Repair method according to one of claims 5 to 8, characterized in that the cooling device ( 6 ) is arranged such that the generated heat flow in the composite component ( 1 ) of the basic body ( 2 ) of the composite component ( 1 ) is directed away. Repair method according to one of the preceding claims, characterized in that the temperature in the composite component ( 1 ) before applying the material ( 5 ) is calculated computer-assisted, and the application of the material ( 5 ) and / or the cooling device ( 6 ) is controlled depending on the calculated temperature. Repair method according to one of the preceding claims, characterized in that the applied material ( 5 ) from the surface of the metal part ( 3 ) in a subsequent operation to create a predetermined surface contour of the composite component ( 1 ) is partially removed again. Repair method according to one of claims 1 to 10, characterized in that the application of the additional material ( 5 ) is carried out in such a way that the surface after application of the material ( 5 ) does not need to be reworked. Composite component ( 1 ) for an aircraft with a basic body ( 2 ) of a fiber composite material and one with the main body ( 2 ) connected metal part ( 3 ), characterized in that the metal part ( 3 ) has been repaired according to one of the repair methods of claims 1 to 12. Composite component ( 1 ) according to claim 13, characterized in that the composite component ( 1 ) is a blade for an aircraft propulsion, and the metal part ( 3 ) is formed by a metal fitting covering the blade at least on the flow inlet side. Device for repairing a composite component ( 1 ) for an aircraft with a basic body ( 2 ) of a fiber composite material and one with the main body ( 2 ) connected metal part ( 3 ), characterized in that the device comprises a cooling device ( 6 ) for heat removal from the composite component ( 1 ) and a facility ( 9 ) for applying material ( 5 ) on the metal part ( 3 ) with the supply of thermal energy. Device according to claim 15, characterized in that the cooling device ( 6 ) is formed by external cooling surfaces, and the cooling surfaces in a fixed spatial allocation to the composite component ( 1 ) stand. Device according to claim 15, characterized in that the cooling device ( 6 ) by at least one of a cooling medium flowed through in the basic body ( 2 ) and / or the metal part ( 3 ) is arranged, and in the device connections for connecting the cooling channel to a coolant supply and a coolant discharge are provided.

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